THE CANADIAN ENTOMOLOGIST. 303 



NOTES ON ELEAS COLLECTED ON RAT AND HUMAN 

 HOSTS IN SAN FRANCISCO AND ELSEWHERE. 



BY R. W. UOANE, STANFORD UNIVERSITY, CALIF. 



In Feb., 1908, Dr. W. B. Wherry, of the Dept. of Public Health of 

 San Francisco, sent to the University for identification a few vials o( fleas, 

 most of which had been collected from rats in the plague-stricken districts 

 and from doctors, nurses and others who had been at work in these 

 districts. Those from the rats showed the following species : Cerato- 

 phyHi^s /asdatus,Bosc., \ $,6 $ 's ; Cfenocephalus cam's {C\.u\\s),'QQktr, 

 2 9 's ; Loemopsylla ( Pulex) cheopis, Rothschild, 16 c^ 's, 19 V 's. Five 

 o 's and one 9 of Ctenopsyllus 7nusciili (Duges), Wagner, were taken 

 from a mouse in the plague laboratory, and 220 specimens of Pulex 

 irritans, Linn., were taken from human hosts or on their clothing in the 

 piague laboratory and hospital and in the refugee camps where human 

 plague cases were of frequent occurrence. A single specimen of an 

 undetermined species of Ceratophylhis was also taken from a human host. 



A later sending from Dr. Wherry, xApril, '08, showed 88 specimens 

 of Ceratophylliis fasciatus and i Ctenopsyllics miisaili from rats, 7 

 Loemopsylla cheopis from mice, 25 Pulex irritaiis and i specimen of 

 Ceratophylliis sp. from human hosts (one P. irritans was from the body 

 of a Chinaman who had died of the plague), and 477 specimens of 

 Ctenocephaliis caiiis collected from a single Dachshund pup. 



From time to time between March ist and June ist, Dr. W. C. 

 Rucker, executive officer of the U. S. Public Health and Marine Hospital 

 Service, has sent me many vials gf fleas taken from rats and humans. 

 These were mostly collected by the small army of rat catchers in the 

 different sections of the city. A summary of all these sendings shows 619 

 specimens of Ceratophylliis fasciatus, 163 specimens of /'?//^.:^; irritajis, 56 

 Ctenopsyllus musculi, 9 Ctenocephaliis canis, and 139 Loemopsylla cheopis 

 from rats, and 668 Pulex irritans and 2 Ceratophylliis fasciatus from 

 human hosts.. 



From February to May, Dr. Snow, of Stanford University, had a 

 man catching rats and mice on the campus in order to determine whether 

 any showed symptoms of plague. 



From the rats were taken 174 specimens of Ceratophylliis fasciatus, 

 62 Ctenopsyllus inusculi, and 8 Hoplopsyllus anomalus, Baker; from the 

 mice, 26 Ceratophylhis fasciatus and 14 Ctenopsyllus fnusculi. 



On examining a number of dead rats in San Jose, that had been 

 brought in for the bounty, I found, on March 14, 7 specimens oi Loemop- 

 sylla cheopis. Only this one lot of rats was examined there. 



August, 1908 



